This is a larger step value (at a lower frame rate), and may appear jerky to the untrained eye. In fact, the object is moving constantly and smoothly but is simply being updated less often.
Bleeeh! It worries me a bit that game developers could fall into putting technical pedantry before consumer experience. If your customer sees a jerky update then your update is jerky - how very clever you might be being in the background really doesn't matter one iota. *I know* you're addressing developers here, but I still think it's genuinely important to bear this in mind: Untrained eyes are the eyes you ultimately have to please.
Other than that, it's mostly good as long as it's taken in this context: You can't win. Either you fix the rate of your game and it falls out of sync with certain monitors or you sync to the monitor and your game runs at different speeds on different boxes. There are benefits and costs associated with whichever method you opt for and how you choose to implement it, and while it would be fantastic to have those benefits and costs collated so folk can make an informed decision, I wouldn't waste any extra time and energy trying to "solve" this logical impass.
I'm not trying to be horrid here, I'm just saying great work, but don't get too caught up on something that isn't really fixable. A comprehensive essay that explains the problem and one's options would be massively valuable in and of itself.
Oh and users that turn vsync off in their card's drivers have opted to see screen tearing... it's not your job to fix that!